/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

package org.apache.iotdb.db.mpp.plan.statement.component;

import org.apache.iotdb.db.mpp.plan.expression.Expression;
import org.apache.iotdb.db.mpp.plan.statement.StatementNode;

import java.time.ZoneId;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;

/**
 * This class maintains information of {@code SELECT} clause.
 */
public class SelectComponent extends StatementNode {

    private final ZoneId zoneId;

    private boolean hasLast = false;

    private boolean hasBuiltInAggregationFunction = false;

    protected List<ResultColumn> resultColumns = new ArrayList<>();

    private Map<String, Expression> aliasToColumnMap;

    public SelectComponent(ZoneId zoneId) {
        this.zoneId = zoneId;
    }

    public ZoneId getZoneId() {
        return zoneId;
    }

    public boolean isHasBuiltInAggregationFunction() {
        return hasBuiltInAggregationFunction;
    }

    public void addResultColumn(ResultColumn resultColumn) {
        resultColumns.add(resultColumn);
        ResultColumn.ColumnType columnType = resultColumn.getColumnType();
        if (columnType == ResultColumn.ColumnType.AGGREGATION) {
            hasBuiltInAggregationFunction = true;
        }
    }

    public void setResultColumns(List<ResultColumn> resultColumns) {
        this.resultColumns = resultColumns;
    }

    public List<ResultColumn> getResultColumns() {
        return resultColumns;
    }

    public Map<String, Expression> getAliasToColumnMap() {
        return aliasToColumnMap;
    }

    public void setAliasToColumnMap(Map<String, Expression> aliasToColumnMap) {
        this.aliasToColumnMap = aliasToColumnMap;
    }

    public boolean hasLast() {
        return hasLast;
    }

    public void setHasLast(boolean hasLast) {
        this.hasLast = hasLast;
    }

    public void setHasBuiltInAggregationFunction(boolean hasBuiltInAggregationFunction) {
        this.hasBuiltInAggregationFunction = hasBuiltInAggregationFunction;
    }

    public String toSQLString() {
        StringBuilder sqlBuilder = new StringBuilder();
        sqlBuilder.append("SELECT").append(' ');
        if (hasLast()) {
            sqlBuilder.append("LAST").append(' ');
        }
        for (int i = 0; i < resultColumns.size(); i++) {
            ResultColumn resultColumn = resultColumns.get(i);
            sqlBuilder.append(resultColumn.getExpression().toString());
            if (resultColumn.hasAlias()) {
                sqlBuilder.append('(').append(resultColumn.getAlias()).append(')');
            }
            if (i < resultColumns.size() - 1) {
                sqlBuilder.append(", ");
            }
        }
        return sqlBuilder.toString();
    }
}
